Method of perforating glass.



R. E. WINNE.

METHOD OF PERFORATING GLASS.

APPLICATION FILED OCT- 9. I917- Patented Dec. 31,1918,

w m e n w n t t m E S w H R Inventor:

UNITED STATES PATENT OFFICE.

ROY E. WINNE, OF SCHENECTADY, NEW YORK, ASSIGNOR TO GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK.

METHOD OF PERFORATING GLASS.

To all whom it may concern:

Be it known that I, ROY E. WV-INNE, a citizen of the United States, residing at Schenectady, county of Schenectady, in the State of New York, have invented certain new and useful Improvements in Methods of Perforating Glass, of which the following is a specification.

My present invention relatesto a method of perforating glass and especially to a method of making very small holes through glass to adapt it for use as a die.

The object of my invention is to provlde a simple, efficient and inexpensive method of making holes through glass whereby a plurality of holes of any desired size may be made simultaneously.

In carrying my invention into effect I heat the glass which is to be perforated until it is plastic and then force through-it a, plurality of wires which are held inparallel and suitably spaced in relation to one another. The glass is then allowed to cool slightly and the wires are withdrawn before it has become hard. If the wires are of a material which is notwet by the glass used they will leave in the glass smooth holes of the'de sired form.

The novel features which I believe to be characteristic of my invention are set forth with particularity in the appended'claims. The manner in which'my invention may be carried into effect however, together with other objects and advantages thereof will best be understood by reference to the following description taken in connection with the accompanying drawing in which Figure 1 is a-perspective of a holder in which the wires to be used may be loosely assembled in the proper relation; Figs. 2 and 3 are perspectives showing the manner in which the wires are fastened into a convenient holder so as to retain the proper relation to one another while the method is being carried out; Fig. 4 is a view of the completed holder; Fig. 5 is a perspective, and Fig;'6 is a cross-section showing the relation of the holder to a die blank while the perforating operation is being carried out; Fig. 7 is a perspectiveof a completed die, and Fig. 8 is an enlarged cross-section through a portion of the die.

In proceeding to carry my inventlon lnto effect I first find it desirable to construct a suitable holder for holding the wire and, in

Specification of Letters Patent.

Patented Dec. 3.1, 1918.

Application filed October 9, 1917. Serial No. 195,613.

case a plurality of holes are to be made simultaneously, retaining all of the wires in proper spaced relation to one another while they are forced through the glass. In constructing sucha holder I first assemble the wires 1 in holes 2 in the disk 3 which may 'be. made of -metal or refractory material. The holes are parallel with one another and s aced in the manner which is desired in the nished product. The disk 3 is then placed inthe'conical opening 4 in the plate 5, both disk and plate resting upon the plate 6 of refractory material. The glass bead 7 on the stem 8 is then heated until it becomes plastic and forced down over the disk 3 until the ends of wires 1 are embedded in the In utilizing the holder thus constructed for making a die a glass blank is placed upon a plate 12 of graphite or other refractory materlal and heated to a temperature at which the bottom of the blank becomes plastic. In the case of lead glass this temperature may be about 800 C. The holder is then inserted in the blank and the wires 1 are forced through the bottom. The blank is then allowed to cool slightly and the holder and wires are withdrawn before the glass becomes hard, each wire leaving a clean hole through the glass. In the case of lead glass the temperature of the glass when the wires are withdrawn may be about 500 C.

In the case of ordinary glass, such for example as lead glass, I find that tungsten or molybdenum wire is especially suitable for making the perforations. This is probably due to the fact that the surface of the :wire is not wet by the glass and that the wire. does not give 01f gas when heated. Wires of'tungsten or molybdenum also do not become as flexible at the temperature at which the operation is carried out as wires of other metals. In case any gas was given; off by the wire bubbles would be formed in the glass and the holes would be imperfect. Y

In some cases it is desirablethat the hole through the glass shall be conical in form instead of cylindrical. The holes may be given a conical form as indicated in Fig. 8, by proper manipulation of the apparatus employed. If the glass is heated to the right temperature the wire, when it is pressed down upon the glass, instead of immediately penetrating the surface will force the surface of the glass down and formia conical depression in the surface. As a result when the wire finally penetrates the under surface While I have described my invention with especial reference to perforating glass for making dies, it will be apparent that it is by no means limited to this particular application but will be of utility wherever it is desired to perforate glass for other purposes. v v 7 What I claimas new and desire to secure -by Letters Patent of the United States is:

1. The method of making a hole through glass which consists in heating the glass 1111- glass throughout the til it is plastic, forcing a tungsten wire through the glass, while it is in that condition allowing the glass to partially cool, and Withdrawing the Wire before the glass becomes hard.

2. The method of making a hole through glass which consists in heating the glass until it is plastic, forcing through the glass while it is in that condition a wire composed of a metal which is not-wet by the glass and which does not give olf gas when heated,

allowing the glass to partially icool and withdrawing the wire before the glass becomes hard.

3. The method of making a hole through lead glass which consists in heating it to a temperature ofaboutf800 0., forcing a tungsten wire through the glass while it is in that condition, allowing the glass to cool to about 500 C. and then Withdrawing the wire.

which consists in heating a glass blank until it is plastic, forcing through the glass while in that condition a plurality of tungsten wires which are held in parallel and suitably spaced relation to one another, allowing the glass to partially cool and with-' drawing the wires before the glass becomes hard.

In witness whereof, I have hereunto set myhand this 8th day of October, 1917.

ROY E. WINNE.

. v 55 4. The method of making a glass die 

